[Samba] samba4 DNS error when joining domain

[steve]

Hi
Joining a lubuntu 11.10 client to the domain I get this:

  net ads join -UAdministrator
  Enter Administrator's password:
  Using short domain name -- POLOP
  Joined 'LUBUNTU7' to realm 'hh3.site'
  No DNS domain configured for lubuntu7. Unable to perform DNS Update.
  DNS update failed!

during the join this all seems OK:

Kerberos: Looking for PKINIT pa-data -- LUBUNTU7$@HH3.SITE
Kerberos: Looking for ENC-TS pa-data -- LUBUNTU7$@HH3.SITE
Kerberos: No preauth found, returning PREAUTH-REQUIRED -- LUBUNTU7$@HH3.SITE
Kerberos: AS-REQ LUBUNTU7$@HH3.SITE from ipv4:192.168.1.24:59014 for 
krbtgt/HH3.SITE at HH3.SITE
Kerberos: Client sent patypes: encrypted-timestamp, 149
Kerberos: Looking for PKINIT pa-data -- LUBUNTU7$@HH3.SITE
Kerberos: Looking for ENC-TS pa-data -- LUBUNTU7$@HH3.SITE
Kerberos: ENC-TS Pre-authentication succeeded -- LUBUNTU7$@HH3.SITE 
using arcfour-hmac-md5
Kerberos: AS-REQ authtime: 2012-04-01T18:05:39 starttime: unset endtime: 
2012-04-02T04:05:39 renew till: 2012-04-02T18:05:20

Then, after:
net ads keytab create
  everyone can work fine.

Just worried about the error message on joining.
Any ideas? Ignore?

Thanks,
Steve